Railway traffic controlling system



Oct. 26, 1937. J. E. WILLING 2,095,930

RAIL-WAY TRAFFIC CONTROLLING SYSTEM Filel May 31, 1935 Signal CircuirSelecTions For fiignala IA'IB and ZA-ZB MM. fizz 44,- ATTORNEY PatentedOct. 26, 1937 UNETED STATES PATENT OiFFlQE Joseph E. Willing, Rochester,N. Y., assignor to General Railway Signal Company, Rochester,

Application May 31, 1935, Serial No. 24,165

10 Claims.

This invention relates to trallic controlling systems for railroads, andmore particularly pertains to the indication of the position of poweroperated track switches in such systems.

The present invention purposes to provide an indicating system wherein apolar-neutral relay is controlled over a polarized circuit in accordancewith the position and locked condition of its associated track switch,as well as the correspondence of such track switch with its controllever. The present invention also provides means associated with thepolar-neutral relay for checking whether or not its polar contacts haveproperly responded in accordance with the polarity applied to itsoperating windings.

Various other features, advantages and characteristic functions of thepresent invention will be in part apparent from the occompanyingdrawing, and in part pointed out as the description thereof progresses.

In describing the invention in detail, reference will be made to theaccompanying drawing which illustrates in a simplified and diagrammaticmanner the circuits and parts of a switch indication system embodyingthe present invention.

With reference to the accompanying drawing, a track switch TS is shownas operated by a switch machine SM which may be of any suitable type,such for example, as disclosed in the patent to W. K. Howe, Patent No.1,466,903, dated September 4, 1923.

Associated with the switch machine SM and track switch TS is a suitablepoint detector contact mechanism PD which may be of any suitable type,such for example, as shown in the patent to C. S. Bushnell, Patent No.1,517,236, dated November 25, 1924. For convenience in describing thepresent invention, the point detector contact mechanism PD is merelyshown as having two movable contacts 3 and 4 each of which cooperateswith three fixed contacts to indicate the three conditions of themovable contacts. The movable contacts 3 and 4 of the point detectorcontact mechanism are jointly operated by the track switch TS and theswitch ciated therewith suitable signals lAiB and 2A2B for controllingtraffic thereover.

The switch machine SM is indicated as controlled by a switch machinecontrol lever SML, which control may be of any suitable type em- 5ployed in interlocking systems, such as shown for example in the pendingapplication or" R. M. Phinney, Ser. No. 539,486, filed May 23, 1931.This lever SML, which is manually operable for the control of the switchmachine SM, is provided with a contact 1 which is included in thecircuits for the relay WP so as to determine whether or not the trackswitch is in correspondence with its lever SML, as described in detailhereinafter.

The point detector contacts PD are connected to the central ofiice bysuitable line wires 5 and 6 which are supplied with energy by a batteryBT located at the track switch.

A switch position indicating relay WP of the polar-neutral type isprovided with two windings, each winding of which, when energized withthe normal potential applied to the line wires 5 and 6 by battery BT,will operate both the polar contacts and the neutral contacts of thisrelay. However, when a resistor 8 is included in series with either ofthese windings the polar contacts of the relay will respond to such adegree of energization, but the neutral contacts will remain in theirdropped away positions. The relay WP may be provided with any requirednumber of polar and neutral contacts, but for the purpose ofunderstanding the present invention only contacts 9, l8 and II have beenshown.

Also, associated with the relay WP are suitable asymmetric units orrectifiers ER and 2B. These asymmetric units are preferably of thecopperoxide type, but it is to be understood that any type of one-wayelectrical valve may be employed in this connection and still be withinthe scope of the present invention.

The relay WP may be employed for any of the purposes required of aswitch position repeating relay in an interlocking system such as theselection of signal circuits, lock circuits and the like, but for thesake of simplicity in the present disclosure, the contacts l0 and I! ofthis relay have been indicated by a legend as included in the signalselecting circuits for the signals IA|B and 2A-2B, which selections maybe made in accordance with any of the usual practices the details ofwhich are unnecessary for an understanding of the present invention.

It is believed that the nature of the invention,

its advantages and characteristic features can best be understood byfurther description being set forth from the standpoint of operation.

Operation With the switch machine control lever SML in a normalposition, as illustrated, the switch ma- 7 chine SM will also be in anormal position locking the track switch TS in a normal position. Thus,the contacts 3 and 4 of the point detector contact mechanism PD are innormal positions, thereby energizing the relay WP over a normalpolar-neutral operating circuit closed from the positive terminal of thebattery BT, through contact i in a normal position, line wire e, polarcontact 9 of relay WP in a right hand position, upper Winding of relayWP, rectifier unit lR in its low resistance direction, switch machinecontrol lever contact '2 in a normal position, line wire 5, contact 3 ina normal position, to the negative terminal of the battery BT.

With energy flowing in this normal polarneutral operating circuit, thepolar contacts of the relay WP are actuated to the right and its neutralcontacts are picked up.

Upon the operation of the control lever SML to a reverse position, it isreadily apparent that the normal polar-neutral operating circuit, abovetraced, is immediately broken by contact i so that the neutral contactsof relay WP drop away. As the rectifier unit 23 is so included in thecircuit as to oppose current flow through the resistance 8 with contact7 in a reverse position, the relay WP is entirely de-energized exceptfor What leakage current the rectifier 2R may permit depending upon itstype and efficiency, it being understood that this value (if present) isvery small and of no practical consequence in this connection.

The switch machine operates the track switch to the reverse position andduring such operation the contacts 3 and 4 are in mid-positions so thatthe energy from battery ET is entirely removed from the line wires 5 and5 which are shunted by the wire !2.

When the track switch TS reaches its reverse locked position, thecontacts 3 and 4 are operated to reverse extreme positions in whichenergy is supplied over the line wires 5 and 6 to relay WP through areverse polar operating circuit closed from the positive terminal of thebattery BT, through contact 3 in a reverse position, line wire 5,contact in a reverse position, rectifier unit 2B in its low resistancedirection, resistor unit 8, upper winding of relay WP, polar contact 9in a right hand position, line wire 8, contact l in a reverse position,to thenegative terminal of the battery ET. The current which fiows inthis reverse polar operating circuit is of insufiicient value to operatethe neutral contacts of the relay WP by reason of the resistance valueof the resistor B, but isof sufficient value to cause the polar contactsof the relay WP to be actuated to left hand positions. It is to beunderstood in this connection that, with the usual construction ofpolarneutral relays, the polar armature will quickly assume its oppositeposition with snap-action like response, but in the event that the polarstructure of the relay to which the present invention is applied doesnot have such characteristics, the contact 9 may be made amake-before-break type contact.

With the polar contact 9 in a reverse position, a reverse polar-neutraloperating circuit is then closed from the positive terminal of thebattery ,BT, through contact 3 in a reverse position, line Wire 5,contact 1 in a reverse position, rectifier unit 2R in its low resistancedirection, lower winding of relay WP, polar contact 9 in a reverseposition, line wire 6, contact d in a reverse position, to the negativeterminal of the battery With the resistor 8 thus excluded from theenergiz-ing circuit of the relay WP, sufiicient current is caused toflow through the lower winding to effect the picking up of the ne tralcontacts of the relay WP. Thus, the relay WP upon the picking up of itsneutral contacts indicates both that its polar contacts have respondedproperly to the polarity applied to the line circuit including wires 5and and that its polar contacts are in positions corresponding to theposition of the contacts of the switch machine control lever Sit-1L.With such a condition existing, the signal circuits for the signalslA-lB and 2A$B will be selected according to the reverse position of thetrack switch, and it will be safe for th movement of traffic inaccordance with such selections subject to the various other automaticsignalling features which may be used in connection therewith.

It is believed that the operation of the system back to its normalcondition will be readily apparent, but for the sake of definiteness thenormal polar operating circuit will be pointed out.

The normal polar operating circuit is closed from the positive terminalof battery BT, through the contact 3, line wire polar contact 9 in areverse left hand position, lower winding of relay WP, resistor 8,rectifier unit HR in its low resistance direction, lever contact '3 in anormal position, line wire 5, contact 3 in a normal position, to thenegative terminal of the battery ET.

The normal polar-neutral operating circuit has already been pointed outabove.

Thus, an indication system for a railway power operated track switch hasbeen. shown and described wherein the relay WP not only indicates theposition and locked condition of the track switch with which it isassociated, but also indicates the correspondence of the track switchwith its control lever as well as the check is the actual response ofits polar contacts to its energizing current.

It should be noted that this embodiment of the present inventionprovides an indication circuit which has all of the protection of theusual polarized circuit, namely, two breaks and two crosses must occurin order to cause a false indication.

It should also be noted that should the polar contacts of the relay WPactually fail to respond, then the neutral contacts will be energizedonly when the lever SML and the track switch TS are in positionscorresponding to the position or" n such polar contacts.

Having thus described an indication system for a railway track switch asone specific embodiment of the present invention, it is desired to beunderstood that this iorm is selected to facilitate in the disclosure ofthe invention rather than to limit the number of forms which it mayassume; and, it is to be further understood that various modifications,adaptations and alterations may be applied to the specific form shown tomeet the requirements of practice, without in any manner departing fromthe spirit or scope of the present invention except as limited by theappended claims.

What I claim is:

1. In combination; a relay having poiar and neutral contacts, said polarcontacts responding to changes in the direction of energization of saidrelay when said relay is energized to one degree,

and said neutral contacts responding to the energization of saidrelay soas to be picked up only when said relay is energized to another degreerelatively higher than said one degree of energization; a two-positioncontrol means; pole changer contacts operable to normal and reversepositions; means energizing said relay to said one lower degree in onedirection or the other depending upon the normal or reverse position ofsaid pole changer contacts; and asymmetric circuit means energizing saidrelay to said another degree onlywhen said two-position control means isin correspondence with said polar contacts of said relay and then onlyif said polar contacts have properly responded to the polarity ofenergization of said relay to said one degree, said means depending uponthe position of said pole changer contacts.

2. In combination, a track switch, a manually operable control lever forgoverning the power operationoi said track switch, a polar-neutralrelay, a line circuit supplied with energy of one polarity or the otherin accordance with the position of said track switch, and circuit meansincluding a polar contact of said relay and a cont ct operated by saidlever to cause said relay to receive 'suijcient energy from said linecircuit to pick up the neutral contacts of said relay only when itspolar contacts are in polar positions corresponding to the polarity ofthe energy supplied to said circuit and only if said manually operablecontrol lever is in a corresponding position, said circuit meansincluding asymmetric means to check the polarity of the energy in saidline circuit against the positions of said polar contacts.

3. In combination, a track switch, a manually operable control lever forgoverning the power operation of said track switch, a polar-neutralrelay, and means including polar contacts of said relay and contacts ofsaid lever for energizing said relay with a polarity in accordance withthe position of said track switch to a degree sufficient to pick up then utral contacts of said relay only when said control lever, said trackswitch and the polar contacts of said relay are in correspondingpositions, said means also including polarity detecting means with whichthe positions of the polar contacts are compared.

4. In combination, a polar-neutral relay having polar and neutralcontacts of which the polar contacts will respond to .a certain degreeof current and of which the neutral contacts will only respond tocurrent of a higher degree than said certain degree, a switch machine, alever for controlling said switch machine, a current limiting elementfor said relay to limit said current to said certain degree, a source ofdirect current, unidirectional current controlling means for energizingsaid relay from said source through said current limiting element bycurrent of a polarity to operate said polar contacts to a differentposition effective only if said lever and switch machine assume acorresponding position, and means including a polar contact of saidrelay to exclude said current limiting element only if such polarcontact assumes a position in correspondence with said lever.

5. In combination, a polar-neutral relay having polar and neutralcontacts of which the polar contacts will respond to a certain degree ofcurrent and. of which the neutral contacts will only respond to currentof a higher degree than said certain degree, two windings for saidrelay, an asymmetric unit of one polarity included in series with one ofsaid windings, an asymmetric unit of the opposite polarity'included inseries with the other of said windings, a polar contact of said relayfor connecting a source of current to one or the other of said windingsdepending on the polar position of said contact, a resistance forconnecting like terminals of said windings together, said resistancebeing of a value so that said relay is energized only to said certainextent if the energizing current must flow through said resistance,whereby current may flow through a winding of said relay without flowingthrough said resistance to cause response of said neutral contact onlyif the polarity of the current flowing and the position assumed by saidpolar contact correspond.

6. In combination, a polar-neutral relay having polar and neutralcontacts of which the polar contacts will respond to a certain degree ofcurrent and of which the neutral contacts will only respond to currentof a higher degree than said certain degree, two asymmetric units, aresistance unit, said asymmetric units, said resistance unit and a polarcontact of said relay being so connected with said relay that current ofsaid certain degree will flow through one asymmetric unit said relay andthrough said resistance when the polar position of said polar contactdoes not conform to the polarity of the current flowing, but wherebycurrent of said higher degree may flow through one asymmetric unit andsaid relay without passing through said resistance if said polar contactassumes a position to conform with the polarity of the current flowing.

'7. In combination, a polar-neutral relay having polar and neutralcontacts of which the polar contacts will'respond to a certain degree ofcurrent and of which the neutral contacts will only respond to currentof a higher degree than said certain degree, an asymmetric unit, aresistance unit, said asymmetric unit said resistance unit and a polarcontact of said relay being so connected with said relay that current ofsaid certain degree will flow through said asymmetric unit said relayand through said resistance when the polar position of said polarcontact does not conform to the polarity of the current flowing, butwhereby current of said higher degree may flow through said asymmetricunit and said relay without passing through said resistance if saidpolar contact assumes a position to conform with the polarity of thecurrent flowing.

8. In combination; two line wires having applied thereto potential ofone polarity or the other from a substantially constant source ofpotential; a relay having polar and neutral contacts, said polarcontacts responding when said relay is energized to one degree or to arelatively higher degree, and said neutral contacts responding only whensaid relay is energized to said higher ole-- gree; a resistor; atwo-position control means; a first circuit means including polarcontacts of said relay, said resistor and said control means for attimes connecting said relay and said resistor in series across said twoline wires, said means being efiective only when said polar contacts areout of correspondence with twoposition control means, whereby said relayis energized to said one degree; a second circuit means including polarcontacts of said relay and said two-position control means for at timesconnecting said relay directly across said two line wires, said meansbeing effective only when said polar contacts and said two-positioncontrol means are in corresponding positions, whereby said relay isenergized to said higher degree; and means allowing current to flowthrough said first and second circuitmeans'only in a particulardirection when said two-position control means is in first and secondcircuit means only in an opposite direction when said two-positioncontrol means is in its other position.

9. In combination; two line wires having energy of one polarity or theother applied thereto from a substantially constant source of potential;a relay having polar and neutral'contacts, said polar contactsresponding when said relay is energized to one degree or to a relativelyhigher degree, and said neutral contacts responding only when said relayis energized to said higher degree; a resistor; a two-position controlmeans; two rectifier units poled in opposite directions; a first circuitmeans including polar contacts of said relay and contacts of saidtwo-position control means for at times connecting said relay and saidresistor in series with one or the other of said rectifier unitsdepending upon the position of said two-position control means, acrosssaid two-line wires, said means being efiective only when said polarcontacts are out of correspondence with said two-position control means;and a second circuit means including polar contacts of said relay andcontacts of said two-position control means for at times directlyconnecting said relay in series with one or the other of said rectifierunits depending upon the position I of said two-position control means,across said two line wires, said means being effective only when saidpolar contacts are in correspondence with said two-position controlmeans; whereby said neutral contacts pick up only when there iscorrespondence between said two-position control means and said polarcontacts and only when said polar contacts have properly responded tothe polarity of the potential applied to said line wires.

10. In combination; a power operated track switch; a manually. operablecontrol lever for governing the operation of said switch; two line wiressupplied with energy of one polarity or the other in accordance with theposition of said track switch; a polar neutral relay; a resistor;rectifier means; and means including said resistor, said rectifiermeans, polar contacts of said relay, and contacts operated by said leverfor controlling the connection of said relay across said line wires soas to cause said relay to receive sufiicient energy to operate its polarcontacts whenever said relay receives energy and so as to receivesuificient energy to pick up the neutral contacts of said relay onlywhen its polar contacts are in polar positions corresponding to thepolarity of the energy supplied to said circuit and only if saidmanually operable control lever is in a corresponding position with saidpolar contacts.

JOSEPH E. WILLING.

